The invention relates to plastic W/O emulsion spreads and fat blends for use therein. The invention particularly relates to fat blends suitable for manufacturing plastic W/O emulsion spreads having a high liquid oil content, little or no hardened fat, substantially no trans-unsaturated fatty acid content and a relatively low level of saturated fatty acids. It also relates to a process for preparing a hardstock that is suitable for use in this fatblend.
For manufacturing plastic W/O emulsion spreads, e.g. margarine, a margarine fat should be used having a well balanced ratio of liquid and solid fats throughout the entire area of use temperatures which usually is from 5.degree. C. to about 20.degree. C.
Historically attempts were made to meet this aim by using blends of natural fats having a sufficient solids content, resulting however in products of unsatisfactory spreadability, consistency and mouthfeel. The use of mixtures of fats hardened to different degrees of saturation is another approach, but for nutritional reasons in recent years the desire is expressed that the level of saturated fatty acids (SAFA) of the component triacyl glycerides of the fats should be kept as low as possible.
W/O emulsion spreads have been on the market for some time aiming to meet this need. Typically, the margarine fat of these products consists of about 87% liquid oil, e.g. sunflower oil and 13% of a hardstock consisting of a randomly interesterified mixture of fully hardened lauric fat, e.g. fully hardened palmkernel oil, and fully hardened palm oil.
In order to allow the use of even less hardstock in the margarine fat, EP 89,082 recommended H.sub.2 M rich hardstocks. The preferred method described in EP 89,082 for producing such hardstock is randomly interesterifying a partly or fully hydrogenated lauric fat having a melting point ranging from 30.degree. to 41.degree. C., with a fat, which can be fully or partly hydrogenated, fractionated or non-fractionated, wherein at least 60% of the fatty acid residues are C.sub.16 - or C.sub.18 -fatty acid residues. This C.sub.16 -C.sub.18 fat is preferably selected from palmfat, soybean oil, groundnut oil, sunflower oil, maize oil, rapeseed oil, having a melting point ranging from 50.degree. to 71 C.; and fractionating the interesterified mixture. Fractionation is preferably done in an organic solvent. The examples of EP 89,082 illustrate spreads comprising margarine fats containing 90 or even 93% sunflower oil and only 7 or 10% hardstock. This hardstock is produced by means of 2 stage fractionation in acetone to obtain a midfraction of a randomly interesterified mixture of 50 parts fully hydrogenated palmkernel fat and 50 parts fully hydrogenated palm fat.
Nowadays there are consumers who express concern about chemically modifying fats e.g. by hydrogenating or hardening, which may result in trans-unsaturation if partial hardening is involved.
To meet the need for spreads with low contents of SAFA in the margarine fat which have been produced without using hydrogenation, CA 2 098 314 proposes to prepare hardstock by chemically interesterifying a blend of generally equal proportions of palm stearin and palmkernel stearin. This hardstock should have the following solid fat contents as measured by AOCS method CD 16-81:
______________________________________ Temp (.degree.C.) % Solids Variance .+-. x % ______________________________________ 5 70.49 2% 10 64.45 2% 20 49.83 2% 25 45.66 2% 30 34.13 2% 35 22.17 2% 40 10.90 2% ______________________________________
To obtain the margarine fat for producing the spread 14-21.1%, preferably 14.5-16%, especially about 16% of this hardstock is blended with the balance of vegetable oil, e.g. olive oil, canola oil and/or sunflower oil.
This approach of CA 2 098 314 results in products with higher SAFA contents and lower cis unsaturated fatty acid (UFA) contents, in particular lower all-cis polyunsaturated fatty acid (PUFA) contents than the products described above, because the balance of SAFA and UFA or PUFA is largely determined by the amounts of hardstock and liquid oil in the margarine fat. This would seem to be the inevitable price to pay for not using fully hydrogenated oils. However, this conclusion is undesirable. There is therefore a need for margarine fats that are as good as the prior art products in respect of nutritional properties as well as the sensoric properties of the resulting spreads, but that have been produced without the use of hydrogenation.